1. Field of the Invention
The present invention relates to a floating habitat that has a dynamic ability to generate its own buoyancy, through the use of external power or by replicating the biotic activity that occurs on wild floating islands. The present invention encompasses a number of different embodiments directed toward providing waterfowl nesting habitat.
2. Description of the Related Art
Naturally occurring floating islands are a relatively unique phenomenon, but they do exist in several places in the world, including Australia, Bangladesh, Fiji, Germany, Hungary, India, Italy, Japan, Mexico, Poland, Turkey, Uganda and the United States. There has been much speculation and some research into how these floating islands form, and the answer appears to be specific to each location. Regardless of how they are formed, once present, floating islands provide a unique habitat for plants and some animal species, and they also play an important role in maintaining the health of the water body in which they are situated.
One of the objects of the present invention is to provide an artificial floating habitat that is similar to a naturally occurring floating island in terms of its aesthetic and functional value. It is a further object of the present invention to solve the problem of maintaining the buoyancy of an artificial floating island over time. Researchers have studied how naturally occurring floating islands maintain their buoyancy and have concluded that gas-producing microorganisms play a pivotal role. See Clark, 2000, infra; Hogg and Wein, 1988, infra. The present invention utilizes this research by incorporating microorganisms into the floating habitat structure as an option.
A naturally occurring floating island serves several purposes, not the least of which is the aesthetic value it adds to a body of water. It also serves as a habitat for various plant and animal species, and it helps purify the water by decreasing algae growth and slowing the natural process of eutrophication. In bodies of water such as ponds and lakes, algae growth and the natural process of eutrophication can lead to an increase in land mass and corresponding decrease in water volume, the killing of fish and other organisms, and the diminishment of aesthetic appearance.
Various floating mechanisms have been devised with the aim of mimicking some or all of the qualities of a naturally occurring floating island. Some examples of commercialized products along these lines are the artificial islands manufactured by Bestmann-Green of Germany, a “rafted floating ecology” produced by Ocean Arks International in Vermont, and a so-called “eco-island” made by MMG Civil Engineering Systems in the United Kingdom. Bestmann-Green has three floating island products—a laminar floating element of “girder” construction with a mat for rooting vegetation, a flexible vegetation unit made up of three triangular elements lying next to each other that are flexibly connected to form a single unit, and a modular system of metal frames with a net stretched within it and a planting mat connected to it. Ocean Arks describes its product as “assemblies of engineered ecologies on floating rafts.” The primary function of their product is to purify wastewater, remove pollutants and digest sludge. The MMG eco-island is a framework of UV-protected PVC tubing with a rot-proof base. Buoyancy is created by watertight tubes that are sealed with specialty caps.
In addition to the products described above, there are a number of patents directed toward floating islands or other floating mechanisms designed to purify water, cultivate plants, dispense fertilizer, or counteract the effect of eutrophication. None of these inventions, however, anticipates the combination of features provided by the present invention.
U.S. Pat. No. 5,799,440 (Ishikawa et al., 1998) discloses a floating island comprising: (i) a planter with holes in it to allow the roots of the plants to grow into the water and to supply water to the soil in the planter; and (ii) an oxygen-generating agent container attached to the bottom of the planter. The planter is made of a foamed resin with a reinforcing film of polyurethane elastomer on the surface. The invention also includes: (i) a layer of porous material on the inner surface of the bottom of the planter that has an aerobic microorganism immobilized in it; and (ii) a plant cultivation bag to hold the soil. In the preferred embodiment, the oxygen-generating agent is calcium peroxide, and the soil in the planter is covered with a net or fabric that is permeable to water and air and is not harmful to the plants. In addition to generating oxygen, calcium peroxide also eliminates phosphorus, thereby restricting algae growth.
U.S. Pat. No. 4,086,161 (Burton, 1978) sets forth an ecological system and method for counteracting the effects of eutrophication in bodies of water such as marshlands, inland ponds and lakes. The system uses clusters of bark fibers positioned in the upper, relatively oxygen-rich zones of such bodies of water. These bark clusters attract and hold excessive nutrient deposition in the form of colloidal wastes and aquatic algae and also provide a safe habitat for algae predators and feeders.
U.S. Pat. No. 6,086,755 (Tepper, 2000) provides a floating hydroponic biofiltration device for use in a body of water containing plant-eating fish. The invention includes a float, a mesh and a matting. The float contains an aperture devoid of soil in which a terrestrial plant is inserted. The mesh is at a substantial depth below the float and serves to enable passage of oxygenated water to the plant roots while excluding large plant-eating fish. The mesh also serves as a substrate surface for the growth of nitrogen-converting bacteria, which convert the ammonia of fish waste to nitrates useful to plants. The matting anchors the plant roots and partially excludes plant-eating fish from a portion of the plant roots. In the preferred embodiment, the mesh and matting are formed of plastic.
U.S. Pat. Nos. 5,766,474 (Smith et al., 1998) and 5,528,856 (Smith et al., 1996) set forth a biomass impoundment management system that uses sunlight to purify water. The main purpose of this invention is to control impurities in water impoundments, such as ammonia, nitrogen, phosphorous and heavy metals. It is well known that nitrogen and phosphorous are primary food sources for various undesirable algae species, and ammonia and heavy metals are toxic to humans, fish and other organisms. This invention aims to purify water by allowing rooted bottom dwelling plants to grow and remain healthy on the bottom of a water impoundment while allowing rootless floating plants to grow and remain healthy above them. The non-rooted, floating plants are contained in a large surface area provided by elongated channels, which are oriented in a North-South direction to take full advantage of the sun. The elongated channels are designed to take advantage of wave activity to increase productivity.
U.S. Pat. No. 5,337,516 (Hondulas, 1994) sets forth an apparatus for treating waste water that includes a waste water basin and a number of wetland plants in floating containers. The idea underlying this invention is that the root systems of the wetland plants will treat the waste water. The extent of growth of the root systems is controlled by an adjustable platform associated with each floating container, so that the aerobic and anaerobic zones within the waste water basin are controlled and can be adjusted or varied as required. Similarly, U.S. Pat. No. 5,106,504 (Murray, 1992) covers an artificial water impoundment system designed to remove biologically fixable pollutants from urban or industrial waste water using aquatic plants to absorb pollutants.
U.S. Pat. No. 4,536,988 (Hogen, 1985) relates to a floating containment barrier grid structure for the containment of floating aquatic plants in a body of water. This invention is designed to facilitate the commercial cultivation and harvesting of aquatic plants. The grid structure consists of elongated flexible sheets that are interconnected at spaced intervals along their longitudinal axes to form a plurality of barrier sections in a web-like arrangement. Through the use of an anchoring means, the barrier grid is tensioned so that certain portions of the structure are submerged beneath the surface of the water by a device that harvests the floating aquatic plants.
U.S. Pat. Nos. 4,037,360 (Farnsworth, 1977) and 3,927,491 (Farnsworth, 1975) disclose a raft apparatus for growing plants by means of water culture or hydroponics. The raft floats on a nutrient solution, and buoyancy of the rafts is increased during plant growth by placing a small raft on a larger raft or on auxiliary buoyancy means. U.S. Pat. No. 5,261,185 (Kolde et al., 1973) also involves an apparatus floating on a nutrient solution. In this invention, rafts are floated in a water culture tank filled with nutrient solution, plant containers are inserted in vertically oriented channels in the raft, and the plants are cultivated by gradually moving the raft from one end of the water culture tank to another.
U.S. Pat. No. 4,487,588 (Lewis, III et al., 1984) addresses a submersible raft for the cultivation of plant life such as endangered sea grasses. The raft is manufactured from standard polyvinyl chloride tubing and fittings.
U.S. Pat. No. 6,014,838 (Asher, 2000) discloses a simple floatable unit for decorative vegetation. U.S. Pat. No. 5,836,108 (Scheuer, 1998) describes a floating planter box comprising a polyhedral planar base member of a synthetic foam resin less dense than water and an optional anchoring means.
U.S. Pat. Nos. 5,312,601 (Patrick, 1994) and 5,143,020 (Patrick, 1992) involve a simple apparatus for dispensing fertilizer in a pond. The invention consists of a flotation structure surrounded by a porous material such as a net sack and an opening in the flotation structure through which fertilizer is dumped. The fertilizer is dissolved by water flowing through the net sack at the bottom of the flotation structure.